ATtiny85 Timer1 deadtime

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Taking a closer look at the Tiny85 Timer and I am wondering
what is the common usage of the deadtime generator?
I have not found a use for that feature yet. Hopefully someone can point out how/why it can be used.

I also see that there are three comparator blocks,
one is associated with the OCR1C register. Do I understand that correctly to be a register value that becomes the value for MAX? I am used to thinking of MAX as the maximum value that the register can hold, ie; 0XFF for an 8 bit register. I always thought of MAX as a fixed value.

It is clear, there are quite a few options in using the
Tiny85 timers.

Thanks.

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are people when Texas executes one.

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tubecut wrote:
Taking a closer look at the Tiny85 Timer and I am wondering
what is the common usage of the deadtime generator?

You would normally use it where you are controlling a pair of driver transistors in a h-bridge configuration. One transistor (e.g. the NMOS between the output and ground) would be switched by the OCnx, while the other (the PMOS between the output and Vcc) would be switched by _OCnx. In this situation, you don't want both of the transistors to be on at the same time, since that would effectively be shorting the supply to ground.

Because of gate capacitance, there's a non-zero delay between the OCnx switching, and the corresponding transistor switching. To ensure that you don't get both transistors on at the same time, you insert a delay between switching off one transistor, and switching on the other. This is what the dead time generator does.

- S

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mnehpets: Thanks. I see that it is really just a programmable delay to activate the output.

Concerning the comparator associated with OCR1C register,
is that just a way to change the MAX value associated with the timer? I am used to thinking of MAX as an absolute
value based on the size of the register. I see this as a way to manipulate the value of MAX?

I'll believe corporations
are people when Texas executes one.

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Quote:

I see this as a way to manipulate the value of MAX?


No, it sets TOP generally. What makes you think that MAX is being modified?

You can put lipstick on a pig, but it is still a pig.

I've never met a pig I didn't like, as long as you have some salt and pepper.

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Quote:
OCR1C holds the Timer/Counter maximum value,

This is from the ATtiny85 manual.

Perhaps I am interpreting that incorrectly(?).

I'll believe corporations
are people when Texas executes one.